(a) Field of the Invention
The present invention relates to a novel bacteriocin, divergicin M35, produced by the Carnobacterium divergens strain M35. The present invention also relates to a composition comprising an effective amount of divergicin M35 and the use of that bacteriocin to kill or limit the proliferation of a microorganism such as L. monocytogenes. 
(b) Description of Prior Art
Lactic acid bacteria (LAB) are food-grade microorganisms used for the production of numerous fermented food products to improve their flavor, texture and shelf-life. LAB produce antibacterial compounds that include organic acids, diacetyl, hydrogen peroxide and bacteriocins, which are known to reduce food spoilage and growth or proliferation of pathogenic bacteria. Use of these naturally produced compounds as food bio-preservative agents has therefore gained increasing attention in the food industry and now represents a promising way to preserve food without chemical agents, especially in ready-to-use products. Bacteriocins may also find use in the preparation of products that are not submitted to sufficient thermal sterilization during their production, since they represent a risk of contamination by pathogenic bacteria such as Listeria monocytogenes, known in the art to be responsible for numerous worldwide outbreaks. The ability of L. monocytogenes to survive longer at refrigerated temperatures and at sodium chloride concentrations up to 10% makes it a serious health threat, particularly in lightly-preserved seafood.
LAB represent the predominant microbial population flora in low temperature stored products. Among LAB that produce antibacterial compounds and that can be used as food-preservative agent, Carnobacteria are particularly attractive since they show interesting physiological characteristics. Indeed, they grow at low temperatures, high sodium chloride concentration and limited carbohydrate concentration, they produce high-antilisterial bacteriocins and have lower acidifying capacities than other bacteriocin-producing LAB.
The prior art reports the isolation and characterization of numerous Carnobacterium bacteriocins such as carnobacteriocins BM1 and B2 (Quadri et al., 1994), divergicin LV13 (Worobo et al., 1995), divercin V41 (Métivier et al., 1998), divergicin 750 (Holck et al., 1996), piscicocin V1a (Bhugaloo-Vial et al., 1996) and carnocin CP5 (Herbin et al., 1997). Although those bacteriocins are known, they were not isolated for the particular purpose of preserving sea food products and their activity spectrum can vary significantly toward pathogen microorganisms. Moreover, only a few studies have reported characterization of bacteriocins from Carnobacterium species isolated from fish and especially those produced by C. divergens strains.
Thereofore, it would be desirable to be provided with a bacteriocin produced by a Carnobacterium divergens strain having anti-listerial activity and capable to grow under conditions encountered in the manufacture and preservation of sea-food products.